Variable gauge trains change the distance between wheels provided to their cars as the cars pass over a gauge changeover device connecting rails different in gauge. The gauge changeover device supports the car body so that the car body does not weigh on the wheels and in that state, moves the wheels in the axle direction along the guide rails so as to change the distance between the wheels. Therefore, the wheels run idle while the distance between the wheels is changed.
When the wheels run idle, the control device of electric trains generally performs idling control to restrict the torques of the main electric motors for stopping the idling state of the wheels.
It is assumed that a collective control system controlling main electric motors with a single inverter is employed with a variable gauge train. As the wheels undergoing change in the distance run idle, the idling control is performed, whereby the torques of all main electric motors controlled by the inverter shared with the main electric motors driving those wheels are restricted.
For example, in the case of a collective control system in which a single inverter controls all main electric motors mounted on a single train car, while the distance between some of the wheels is changed, the torques of all main electric motors of the train car to which those wheels are provided are restricted. Therefore, almost no driving force is obtained from the train car of which some wheels are undergoing change in the distance. Consequently, the driving force of the entire train may significantly drop while the distance between the wheels is changed.
Patent Literature 1 discloses a variable gauge motor train car control device employing an individual control system for properly controlling the driving force of the wheels during the gauge changeover operation. The individual control system is a system controlling a single main electric motor with a single inverter.